Inverted U

Inverted U may refer to:


 * Calmfors–Driffill hypothesis, an economic theory describing the relationship between collective bargaining and employment
 * Kuznets curve, an economic theory describing the relationship between income per capita and wealth inequity
 * Yerkes–Dodson law, a concept in psychology, describing the relationship between arousal and performance
 * ∩ (U+2229 in Unicode); also $$\cap$$, the mathematical symbol for Intersection (set theory)
 * A shape used to describe narrative structure, specifically the shape for a tragedy